Justin Stewart (they/he)


I am interested in the ecological and evolutionary processes that control how microbial communities assemble and function across diverse environments. Likewise, my research involved geospatial analyses of how communities vary across time and space. I do this using molecular, remote sensing, and advanced statistical-machine learning methods backed by theoretical ecology.

During my Masters I focused on the biogeography of the atmospheric microbiome and the built environment. For this I climbed roofs and walked subways sampling the near-surface atmosphere and applied molecular and computational methods to identify patterns of biodiversity. I married this with remote sensing analysis of three-dimensional urban structure.

During my PhD I explore the global evolutionary biogeography of underground networks using experimental, geospatial, and statistical modelling approaches. I will identify how plant root microbiomes assemble across diverse taxa and how this differs from domesticated and wild crops. Specifically plants will be stressed through nutrient deprivation as to shift microbiome structure.

Selected Publications

Recent Advances in Understanding the Ecology of the Lung Microbiota and Deciphering the Gut-Lung Axis.  K. A. Willis, J.D. Stewart, Namasivayam Ambalavanan https://doi.org/10.1152/ajplung.00360.2020

Variation of Near Surface Atmosphere in PM 2.5 Associated Microbial Communities at an Urban and a Suburban Site in Philadelphia, PA, USA Region. J. Stewart, K. Shakya. https://doi.org/10.1016/j.scitotenv.2020.138353

Noise Pollution in Philadelphia Neighborhoods During Summer 2017. Environmental Pollution, 2019. K. Shakya, P. Kremer, K. Henderson, M. McMahon, R. Peltier, S. Bromberg, J. Stewart. https://doi.org/10.1016/j.envpol.2019.113195

Outdoor Atmospheric Microbial Diversity is Associated with Three-Dimensional Urban Landscape Structure and Differs from Indoor-Transit Systems. J.D. Stewart, P. Kremer, M. Conway, K. Shakya. A. Saad (In Review) PrePrint: https://www.biorxiv.org/content/10.1101/2020.06.17.157651v1

Functional Redundancy in Local Spatial Scale Microbial Communities Suggest Stochastic Processes at an Urban Wilderness Preserve in Austin, TX, USA. J.D. Stewart, K. Yusoof, T. Bilinski. (In Review) PrePrint: https://www.biorxiv.org/content/10.1101/2020.06.25.171660v1

Link to full publication list in PURE